Has FinancialData forgotten how to deliver monthly data?

I seem to get odd results from the following FinancialData code:

FinancialData["SP500", "Jan. 1, 1978", "Month"]

This gives me a TimeSeries of 11,372 "Daily" data points.

I expected to get ~460 "Month" values, similar to what I get from the following WolframAlpha query:

WolframAlpha["United States 30 year treasury bond monthly", {{"History:Treasury:EconomicData", 1}, "TimeSeriesData"}];Length@%460

I haven't done this in a while, but FinancialData didn't used to do this. This seems like something that has appeared in FinancialData since it began outputting TimeSeries objects.

I know I can extract the monthly data from the TimeSeries, just seems odd.

Have I missed something?Thoughts|suggestions appreciated.